1. Field
Example embodiments relate to tunneling field-effect transistors (TFETs) including graphene channels, and more particularly, to TFETs in which a gate voltage is applied to tunnel carriers through a semiconductor between a graphene channel and an electrode.
2. Description of the Related Art
Graphene having a two-dimensional hexagonal carbon structure may replace semiconductors in some electronic devices. Recently, worldwide studies about graphene have been conducted. When graphene having a zero gap semiconductor is manufactured as a graphene nano-ribbon (GNR) that has a width of less than or equal to 10 nm, a band gap is formed in the GNR due to size effect, and thus, a field-effect transistor (FET) operating at room temperature may be prepared using the GNR.
When a graphene transistor using a GNR is prepared, an on/off ratio of the graphene transistor may increase, but a mobility in the GNR may decrease due to a disordered edge of the GNR. As a result, an on-current of the graphene transistor may be low. Alternatively, a vertical electric field may be applied to a bilayered graphene to form the band gap. However, it may be difficult to grow a uniform bilayered graphene using large-area chemical vapor deposition (CVD).